Pasadena Fire and assisting agencies responded to the blaze in the 2000 block of North Raymond Avenue shortly before 5 a.m. First arriving units reported an exterior fire with extension into the interior and attic space of a one-story home.
The incident was quickly upgraded to a second alarm, and it took about 40 minutes to knock down the blaze, according to officials.
Six occupants were displaced by the fire, but no assistance was requested for temporary housing.
Agencies that assisted included Glendale Fire, San Marino Fire, LA County Fire, Orange County Fire Authority, Pasadena police, and one City of Pasadena Building Inspector.
The cause of the fire remains under investigation.